Format of PCI Capabilities List:
Offset Size Description )
00h BYTE capability identifier
01h PCI Power Managment
01h BYTE offset of next item (within configuration space) or 00h
N BYTEs varies by capability type
---PCI Power Management---
02h WORD power managment capabilities (see #00885) (read-only)
04h WORD power managment capabilities status register (see #00886)
06h BYTE PMCSR bridge support extensions (see #00887)
07h BYTE (optional) read-only data register (see #00888)
Note: this information is from the v0.93 draft of the specification and is
subject to change
SeeAlso: #00878,#00880